<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document2</title>
    <style>
        .three input:focus {
            color: red;
        }
    </style>
</head>
<body>
    <div class="three">
        <input type="text">
        <input type="text">
        <input type="text">
        <input type="text">
    </div>

    <div class="two">
        <input type="text">
        <input type="text">
        <input type="text">
        <input type="text">
    </div>

</body>
</html>